To wear an ipod while shitting in a public restroom in order to distract the mind from the potential embarassment of making loud, wet bowel movements. Also confers the added benefit of muting the bowel sounds of fellow shitters.

Can be used as both noun and verb.

(Marcel puts on headphones)
Corey: Dude, you going to the gym?
Marcel: No, i'm going to go take an iShit.

As Aaron sat on the toilet, he heard the faint tracings of "Liberian Girl" by Michael Jackson echoing off the bathroom walls. He instantly knew that Marcel was in the stall next to him, iShitting.